// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_SPDY_SPDY_HEADERS_HANDLER_INTERFACE_H_
#define NET_SPDY_SPDY_HEADERS_HANDLER_INTERFACE_H_

#include <stddef.h>

#include "base/strings/string_piece.h"
#include "net/base/net_export.h"

namespace net {

// This interface defines how an object that accepts header data should behave.
// It is used by both SpdyHeadersBlockParser and HpackDecoder.
class NET_EXPORT_PRIVATE SpdyHeadersHandlerInterface {
public:
    virtual ~SpdyHeadersHandlerInterface() { }

    // A callback method which notifies when the parser starts handling a new
    // header block. Will only be called once per block, even if it extends into
    // CONTINUATION frames.
    virtual void OnHeaderBlockStart() = 0;

    // A callback method which notifies on a header key value pair. Multiple
    // values for a given key will be emitted as multiple calls to OnHeader.
    virtual void OnHeader(base::StringPiece key, base::StringPiece value) = 0;

    // A callback method which notifies when the parser finishes handling a
    // header block (i.e. the containing frame has the END_STREAM flag set).
    // Also indicates the total number of bytes in this block.
    virtual void OnHeaderBlockEnd(size_t uncompressed_header_bytes) = 0;
};

} // namespace net

#endif // NET_SPDY_SPDY_HEADERS_HANDLER_INTERFACE_H_
